Piston



Patented lz'eb., 23, i926,

MICHAEL H. SULLXVAN, 0F lJOUG-HKEESIE, NEXV YRK.

PISTON.

Application filed April 29, 1925. Serial No. 26,758.

To all whom, it may concern;

Be it known that l, MICHAEL l-l. Sunnivnn, a citizen of the United States, resid-l ing at Poughkeepsie, in the county oi Dutchess and State oi New York, have 1nvented certain new and useful improvements in Pistons; and l do declare the foilowing to be a full, clear, and exact description ot the invention, such as will enable others skilled in the art to which it appertains to` make and use the same.

This invention which relates to pistons is particularlyV applicable to that type of hollow pistons which have sectional piston or pacliing rings held in tioht contact with the cylinder wall by means of springs, Herstefore it has been the practice t employ coiled springs for this purpose, but this is no longer necessary, as according to t-he present invention, the packing ring sections are held in tight contact with the cylinder wall by means oi bowed or substantially U-shaped springs which to a certain extent follow the inner wall of the piston and therefore leave more room for the end of the connecting rod.

The advantages for this improved construction are numerous. For instance, a piston constructed in accordance with the present invention may be nia-de entirely by a die casting process. This was not true ot the other types of similar pistons which have heretofore been employed, and theretore the present type oit piston is much easier and cheaper to make than the other types. Furthermore, according to the pres- `ent invention, all springs which are used in a give piston are exactly the same size and are ot exactly the same strength, so that they act to keep all sections of the piston ring under exactly the same pressure in contact with the cylinder wall. Thus, the improved spring means acts so as to keep the piston centered within the cylinder to a greater extent than the heretofore known types ci pistons in which coiled springs were employed.

rlhe invention will be more readily under stood by reference to the following detailed description taken in connection with the accompanying drawing.

ln the accompanying drawing Fig. l is a horizontal sectional view et a pist-on constructed in accordance with the present invention, taken substantially on v jections 14 fitting the plane indicated by the line l-l of Fig. 2;

Fig. 2 is a vertical or longitudinal sectional view of the piston, taken substantially on the plane indicated by the line oi' Fig. l; and

Fig. 3 is a perspective view et one ot' the improved springs with which the piston is equipped, one end of this spring being shown coupled to one of the plungers Yfor forcing one et the piston ring` sections in contact with the cylinder wall, while another ot the plungers is shown about to be connected with the other end of thek spring.

lin the illustrated embodiment of the invention, the numeral l designates a hollow piston having an integrally formed head 2 at one end and having a pair` of peripheral grooves 3 cut or disposed in its outer wall adjacent the head 2, to receive sectional pis ton or packing rings 4l. Asshown particnlarly in Fig. l of the drawing, each oit these rings Llis composed of two semi-circular sections 5, the ends of which are bridged by sealing blocks G. The sealing blocks (3 lit in recesses 7 formed in the outer wall ot the piston l adjacent the grooves 3, and are provided with ribs 8 litting in channels 9 `:termed in the ring sections 5. All ot this structure is now old in the art and forms no part of the present invention.

The piston l is also provided as usual with trunnions l() toreceive the pin upon which the connecting rod is connected.

According` to the lpresent invention, the piston isl provided with short inwardly eirtending hollow bosses disposed opposite the packing ring grooves 3 and two ot them are provided for each groove. The bosses foreach groove aredis posed at diametrically opposit-e sides of the piston, and the bosses of one groove are disposed at right angles to the bosses of the other groove.

Disposed in the bosses 1l are plungers 12, the outer ends of which are cut away from one side as at 13 and are provided with proin recesses provided in the sections 5 of the packing rings 4. In this way, the plungers l2 are connected to the sections V5 of the packing rings. The inner ends of the plungers project beyond the inner ends of the bosses ll and are formed with notches l5 and also with apertures l5, the purpose of which will hereinafter be described.

l1. These bosses are Instead ot having coiled springs surrounding the plungers 12 to torce the saine outwardly as Was heretofore the practice, the present invention contemplates the use of curved or U-shaped springs 17. These springs may be inade ot any suitable material, but are preferably -formed t'roir1 strips ot' spring wire. At their ends, the springs 17 are i'orined into eyes 18. Portions ot these eyes are intended to lit into the notches 15 formed in the inner ends ot the plungers 12 as shown in portions ot' the eyes 18 extend around portions et the plungers. After the springs 17 have been assembled .Vith reference to the plunger-s in this inanner, cotter pins 19 are inserted through the apertures 16 to prevent the eyes 18 of the springs 17 lroin hccoming` disengaggec. troni the inner ends ot the plungers 1?.

ln a. piston constructed illustrated in the drawing, there are tiv'o ot' the springs 1T. Qne spring has its nds enforced with the diainelirically opposi e plungers 'l2 tor the AWo complementary sectios 5 o one ot the packing rings Il, other spring While connected to the diainetrically opposite plungers of the sections or the other peel:- ing' ring. Both springs follow to some eX- tent the contour ot the inner Wall ot the hollow piston 1, and therefore leave a considerable central space Vin the piston to provide room tor the connecting rod which, as hereinheiore explained, is coupled to a pin inounted in the trunnions l0.

Frein the foregoing description taken in connection With the acconipanyingt,T drawing. the construction, purpose and advantages of the invention will he readily understood so further explanation is not necessary, hut nevertheless it Will he stated that hy the use ot the curved or licl-shaped springs 17, all ot the sections 5 ot the packingV rines will he under exactly the sante amount otV pressure and therefore the piston Will be centered in the. cylinder. Furthermore, since to providefor the improved type ot piston, only two short hollow bosses' 11 are necessary. the entire piston niay he made hy a die-casting process at less expense andin an easier manner than heretofore known tne drawing, While other out departing` t'roin the meaning ot the apperded claims.

piston construction, the combinat l li-ollonr piston provided .vith a packing` ring; groove in its outer wall, hollov cosses extending inwardly troni the inner Wall oi said piston, said bosses being dianietrically disposed and coinnninicating with sad groove, a packing ring disposed in groove ant. composed of sections, f dispose:y Vin said bosses and conneceo to the sections ot' said ring, and a curved spring tolle-Wing the inner contour oit said. cylinder and having,l its ends conneeteL to the inne-r ends ot said plungers.

fn a piston construction. the combi ation ot" a hollow piston provided with a inner Wall ot' said pston, said bosses being diainetricaily disposed and communicating Yn'ih said groove, a packing ring disposed in `groove composed ot sections, plungrers disp d in said bosses and connected to the. sections ot said ring, the inner ends oi sar' l plunger-s projecting beyond the inner ends o vsaid bosses and provided with notches, and a. curved spring tollowi g the contour ot the inner Wall o'l' said piston and having its ends disposed in said notches and fornied sith eyes extending around portions ot said pli.. rs, and ineens tor maintaining the ends ot said spring in said notches.

ln testimony Whereotl l have hereunto attixed my signature.

MGHA JL H. SULLIVAN.

eid

changes of this nature may he 

